A semiconductor device having a trench gate structure is one form of a power semiconductor device. In a power semiconductor device, a semiconductor element such as a MOSFET (Metal Oxide Semiconductor Field Effect Transistor), an IGBT (Insulated Gate Bipolar Transistor), or a SiC-MOSFET is formed on a semiconductor substrate. An interconnection (for example, a gate interconnection and the like) and an electrode (for example, an emitter electrode and the like) for operating such a semiconductor element are formed in the semiconductor device.
The interconnection and the electrode are disposed at a distance from each other. A protective film is formed to cover a region located between the interconnection and the electrode. Further, a solder layer is formed to cover the protective film. PTD 1 and PTD 2 are examples of patent documents disclosing this type of semiconductor device.